Pneumatic tool



J. A. MONNIER ET AL PNEUMATIC TOOL Filed Jan. 28, 1937 INVENTOR. l2Iva/Irma? 00w 6. .BRms r ATTORNEY Aug. 23, 1938.

p f F Q ha x QF Eu w able gaseous fluid under pressure.

Patented Aug. 23, 1938 PATENT, OFFICE PNEUMATIC TOOL James A. Monnierand Corning S. Brush, Algonac, Mich.

Application January 28, 1937, Serial No. 122,703

4. Claims.

Our invention relates to a new and useful improvement in a pneumatictool of the rotary type, whereby a driven shaft to which a suitable toolsuch as a grinding wheel or the like may be attached is rotated. Whilethe invention is referred to as a pneumatic tool and is primarilyintended for being driven by air, it will appear obvious from thedescription of the invention that it might also be driven by steam orother suit- It is an ob ject of the present invention to provide a toolof this class so constructed and arranged that the maximum. speed of thetool is automatically governed so that when the tool is lifted from thework piece upon which an operation is being performed a racing of thetool will be prevented.

' Another object of the invention is the provision of a tool of thisclass so arranged and constructed that by simple and easy adjustment thevolume of driving fluid delivered to the tool may be regulated.

Another object of the invention is the provi sion of a rotor slidablymounted on a rotatable shaft which it serves to rotate, and so arrangedand constructed that, when in operation, the sliding of the rotor ontheshaft will be controlled by the speed of rotation.

Another object of the invention is the provision in a tool of this classof a circular'rotor mounted on the shaft which it drives and cooperatingwith a jet ring or fluid distributor so-that the fluid will be deliveredto the rotor around its periphery.

Another object of the invention is'the provision in a tool of this classof a rotor having a plurality of inwardly directed passages openingoutwardly at its periphery and communicating at their inner ends withlaterally directed inclined passages through which the driving fluid maybe delivered.

Other objects will appear hereinafter.

The invention consists of the combination and arrangement of partshereinafter described and claimed.

The invention will be best understood by a reference to the accompanyingdrawing which forms a part of this specification and in which,

Fig. l is a longitudinal central sectional view of theinvention.

Fig.2 is a fragmentary sectional View taken on lined-2 of Fig. l.

Fig. 3 is a fragmentary sectional view taken on line 33 of'Fig. 1.

Fig.4 is a sectional view taken on line 4-4 of Fig. l'with parts brokenaway.

Fig. 5 is a sectional view taken on line-5-5 of Fig. 1.

Fig. 6 is a side elevational view, slightly reduced, of the jet ring.

Fig. 7 is a fragmentary sectional view taken on line 7- of Fig. 1.

As shown in the drawing, the invention comprises a housing having anelongated neck l5 which serves as a hand hold and which terminates inthe enlarged cup-shaped portion I6. Extending axially of the housing isthe driven shaft ll, on the enlarged portion 18 of which is mounted abearing l9 held in position by the nut 20 and clamped against the nut 20by the collar 25 which is threaded on the end of the neck I5. On the endof the shaft is a suitable collet head 22 whereby a suitable tool suchas a grinder, cutting tool or the like may be mounted.

The shaft ii is also journaled in the bearing 23 and mounted on the rearend of the shaft I1 i a bushing 24 having at one end the head 25 whichis provided with the tapered surface 26 and in which are formed spacedopenings 21 in each of which is positioned a ball 28 adapted to engagethe inclined surface 29 formed at one end of the collar 30. This collaris slidably mounted on the bushing 24 but is non-rotatable thereon. Thecollar 3|] and the bushing 24 are keyed by the key 32 and the bushing 24is mounted on the shaft IT. as a press fit so that the collar and thebushing 2- 5 both rotate in unison with the shaft ii. A cup-shapedfitting 33 is threaded on the inner end of the shaft I! and overlies theend of the collar 39. A spring 34 is positioned about the bushing 24 inembracing relation and engages at one of its ends with the end of thecollar and at its other end with, the inner face of the fitting 33.Consequently the sliding of the collar 36 on the bushing 24 toward theright of the drawing would be against the compression of the spring 36,so that the spring 34 would normally retain the parts in the positionshown in Fig. Fixedly mounted on the collar 30 is a rotor 35 which iscaused to rotate by a fluid under pressure delivered thereto. As therotor rotates and carries with it the shaft H, the centrifugal forceoperating on the balls 28 would have a tendency to force them outwardly.When this force becomes sufiiciently strong resulting from the increasedspeed of rotation the balls will move outwardly and force the collar 30to move toward the right of the drawing against the compression of thespring 34, thus diminishing the quantity of fluid delivered to the rotorand therefore reducing the speed of the rotor.

Positioned fixedly within the housing [6 so as to embrace the rotor 35is a cylindrical member which may be termed a jet ring 36. Formed in thejet ring at spaced intervals are the axially extended passages 31. Eachof these passages 37 communicates with an arcuate groove 39 formed inthe periphery of the jet ring 36. Each of these grooves 39 terminatescentrally of the jet ring 36 and communicates with the chordallydirected passage All which opens through the inner surface of the ring36.

Formed in the periphery of the rotor 35 is a plurality of spacedrecesses M, each of which communicates with a pair of oppositelydirected passages 42 and 53, which are directed at an incline to thefaces of the rotor 35 and outwardly toward the periphery. Thus airdelivered through the passages 3i will be projected outwardly throughthe passages ii and 43 and effect a rotation of the rotor 35. In orderto permit the exhausting of the air passing outwardly through thepassages at, we have cut openings 44 as spaced parts on the ring 36,leaving a body 45 of the material spanning the cut away portion and thisbody 35 is the portion of the ring 36 which registers with the rotorThreaded on the housing it and serving as an end wall or a closuretherefor is the cap 55 in which are formed the pockets 4'5. Positionedin the pockets l? is a spring 48 and a ball 4% adapted to bear againstthe inner face of the adjusting plate 56 which is held in position bythe spring band 5% snapped on the hub 52 of the cap il'z. This adjustingplate 56 carries the inwardly projecting stud 53 which projects throughthe arouate slot 54 formed in the cap 46. This stud projects into apocket 55 formed in the control valve 56. This control valve is circularand fits fairly snugly within the housing 56. Formed centrally of thecontrol valve 53 in one face thereof is a recess 5'? which communicatesby passages 58 with the slots 5% 68 and 5!, which open through one facethereof. Projecting outwardly from one face of the valve 5% is acircular flange engaging in a circular groove 63 formed on the innerface of the cap 45. The construction is such that upon rotating theplate 5f] the valve 56 may be rotated.

Formed in the hub 52 is a threaded opening 64.

to which may be attached the end of the pressure line through which thedriving is conducted. This driving fluid will pass through the pipe 65mounted in the cap it, this pipe 65 traversing the recess 6% formed inthe hub 52. A filling passage 6! closed by the plug 68 is provided fordelivery of oil into the passage or recess 66. This oil may be drawnthrough the openings 69 and '50 into the passage 5? so that the airdelivered to the jet ring 36 will be lubricated.

When the plate 5:? is rotated to a certain posi-- tion, the slot 6i willbe in registration with one of the passages 3i and the slots 59 and willnot be in registration with any of the passages 31, so that the drivingfluid will be delivered to the rotor through only one of the passages3?. Should it be desired that more power be transmitted to the rotor theplate 5E3 may be rotated until the slot 60 is also brought intoregistration with one of the passages 37!, the slot ti being ofsufficient length to permit this rotation without disturbing thedelivery of fluid through the slot iii. In such a position of control oradjustment, the fluid will be delivered to the rotor through a pair ofpassages 31. Should additional fluid be desired so that additional powerwould be transmitted to the rotor the plate 50 may be turned to bringthe slot 59 into registration with one of the passages 37 while, at thesame time, the slots 60 and iii would remain in registration with theirrespective passages 31 and thus the driving fluid would be transmittedto the rotor through three of the passages 31. In this way, there isprovided a simple and easily operated means for adjusting the amount offluid under pressure delivered to the rotor.

When the tool is operating, the power required to drive the tool at therequired speed would, of course, depend upon the nature of the toolmounted on the head 22 and the nature of the work being done. On sometypes of work greater power would be required than on others and theadjusting feature referred to affords a meansv of regulating this power.The ball t9 would at each position of adjustment snap into a shallowrecess it formed in the inner face of the plate 50.

When the tool is operating and it is lifted from the work the shaft I!would be, of course, be relieved of the strain or resistance which theoperation would exert and the shaft ['1 would naturally have a tendencyto race. When the increased speed reaches a predetermined amount. theballs 23 moving outwardly would shift the collar to the right carryingwith it the rotor 35, thus moving the recess 41 gradually out ofalignment with the jet passages 40 and therefore reducing the amount offluid under pressure delivered to the rotor. Consequently, when the toolis lifted from the Work piece, its speed of rotation cannot pass apredetermined speed as the control automatically functions.

With a tool constructed and arranged in this manner, it is believed thata very efficient easily operated tool of this class is provided, inwhich a maximum of control and regulation is obtained while, at the sametime, the device is compact and yet durable.

While we have illustrated and described the preferred form ofconstruction, we do not wish to limit ourselves to the precise detailsof structure shown, but desire to avail ourselves of such variations andmodifications as may come within the scope of the appended claims.

Having thus described our invention, what We claim as new and desire tosecure by Letters Patent is:

1. In a machine of the class described a housing; a rotatable shaftprojected into said housing; a rotor mounted on and rotatable in unisonwith said shaft; a fluid delivery member embracing said rotor and havinga plurality of passages formed therethrough centrally thereof inregistration with said rotor and communicating with passages openingthrough one of its end faces; means for delivering fluid to saidpassages opening through said end faces, a portion of said fluiddelivery member being cut away at opposite sides of said rotor andprovided with a cut away portion spanning said rotor for permittingescape of fluids from one side of said rotor.

2. A tool of the class described, comprising: a housing; a rotatableshaft projected into said housing; a rotor mounted on and rotatable inunison with said shaft and having a plurality of spaced recesses formedin its periphery, each of said recesses communicating at its base with apassage opening at one of the side faces of said rotor and directed atan incline to said shaft and inclined outwardly toward the periphery ofsaid rotor; an annular member snugly embracing said rotor and having anaxially directed passage opening through one of its end faces andcommunicating at its inner end successively with the recesses in theperiphery of said rotor upon rotation of said rotor; a valve positionedin said housing and having a plurality of passages formed thereinadapted for communicating with the ends of said passages in said annularmember; means for conducting fluid under pressure to the passages insaid valve, said valve and said annular member being rotatably,relatively movable for regulating the volume of fluid delivered to thepassages in said annular member.

3. A tool of the class described, comprising: a housing; a rotatableshaft projected into said housing; a rotor mounted on and rotatable inunison with said shaft and having a plurality of spaced recesses formedin its periphery, each of said recesses communicating at its base with apassage opening at one of the side faces of said. rotor and directed atan incline to said shaft and inclined outwardly toward the periphery ofsaid rotor; an annular member snugly embracing said rotor and having anaxially directed passage opening through one of its end faces andcommunicating at its inner end successively with the recesses in theperiphery of said rotor upon rotation of said rotor; a valve positionedin said housing and having a plurality of passages formed thereinadapted for communicating with the ends of said passages in said annularmember; means for conducting fluid under pressure to the passages insaid valve, said valve and said annular member being rotatably,relatively movable for regulating the volume of fluid delivered to thepassages in said annular member; and means accessible exterior of saidhousing for effecting relative movement of said valve and said annularmember.

4. In a. tool of the class described, a housing: a rotatable shaftprojected into said housing; a rotor mounted on and rotatable in unisonwith and axially movable of said shaft; a spring for normally resistingmovement of said rotor on said shaft in one direction; a stationarydelivery member having a plurality of passages formed therein fordelivering fluid to said rotor, said rotor having a plurality of spacedrecesses formed in its periphery for reception of fluid delivered bysaid delivery member; a plurality of curvilinear members loosely mountedon said shaft in circumferentially spaced relation to each other andadapted upon rotation of said shaft in excess of a predetermined speedfor moving outwardly from the periphery thereof; and means cooperatingwith said curvilinear members, upon their outward movement, forefiecting axial movement of said rotor relatively to said shaft againstthe compression of said spring.

JAMES A. MONNIER.

CORNING S. BRUSH.

